174 Mechanisms of Injury as a Diagnostic Predictor of Sport-Related Concussion Severity in Football, Basketball, and Soccer: Results From a Regional Concussion Registry.

INTRODUCTION: Through a single-institution sport-related concussion (SRC) registry, we sought to: (1) provide a descriptive analysis of mechanisms of SRC in football, basketball, and soccer and (2) determine if mechanism of injury was associated with symptom duration.

METHODS: A retrospective cohort study was conducted through in-depth patient interviews. Complete data were collected for 295 patients. Mechanisms were stratified into 3 components: a contact mechanism, a player mechanism, and an awareness mechanism. For each sport, each mechanism was compared via 1-way χ analyses. Symptom duration data were represented with Kaplan-Meier survival plots and Cox proportional hazards models to estimate the relationship between the exposure (concussion mechanism) to the time variable outcome (days of symptom duration).

RESULTS: The majority of athletes were male (70%) with an average age of 15.9 (±2.0) years. Football was the most represented sport (51%). The most common contact mechanisms were helmet-to-helmet contact in football (74%), ground/equipment in basketball (40%), and player to head in soccer (33%). Helmet-to-helmet contact was significantly overrepresented in football (χ = 69.267, df = 2, P < .001). Within the player mechanism, tackling (33%) and blocking (32%) predominated in football, rebounding (45%) and defense/loose-ball (33%) were most common in basketball, and challenging a player (44%) along with the act of heading (40%) were most commonly reported in soccer. Within the awareness mechanism, basketball (χ = 8.805, df = 1, P = .003) and soccer (χ = 11.255, df = 1, P = .001) players were more likely to be unaware of the oncoming collision. For soccer, being unaware of the oncoming collision was associated with a 2.54 (95% confidence interval, 1.14-5.69) times increased risk of not achieving asymptomatic status.

CONCLUSION: The current study analyzed mechanisms of SRC via a regional sports concussion outcomes registry. In middle school, high school, and collegiate athletes: (1) a helmet-to-helmet collision was most common football mechanism; (2) ground and surrounding equipment and player elbows predominated in basketball; (3) challenging a player and heading were the most common mechanisms of SRC in soccer; and (4) "awareness" of an oncoming collision in soccer was the only mechanism associated with a decreased the risk of prolonged symptom recovery.